05000424/LER-1917-002, Regarding Wiring Error Results in Automatic Actuation of a Safety System
| ML17117A329 | |
| Person / Time | |
|---|---|
| Site: | Vogtle  |
| Issue date: | 04/27/2017 |
| From: | Taber B Southern Nuclear Operating Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| NL-17-0664 LER 17-002-00 | |
| Download: ML17117A329 (4) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 10 CFR 50.73(a)(2)(iv)(A), System Actuation 10 CFR 50.73(a)(2)(ii)(A), Seriously Degraded 10 CFR 50.73(a)(2)(viii)(A) 10 CFR 50.73(a)(2)(ii)(B), Unanalyzed Condition 10 CFR 50.73(a)(2)(viii)(B) 10 CFR 50.73(a)(2) 10 CFR 50.73(a)(2)(x) 10 CFR 50.73(a)(2)(v)(A), Loss of Safety Function - Shutdown the Reactor 10 CFR 50.73(a)(2)(v)(B), Loss of Safety Function - Remove Residual Heat 10 CFR 50.73(a)(2)(v), Loss of Safety Function 10 CFR 50.73(a)(2)(i)(A), Completion of TS Shutdown 10 CFR 50.73(a)(2)(1) 10 CFR 50.73(a)(2)(vii), Common Cause Inoperability |
| 4241917002R00 - NRC Website | |
text
~ Southern Nuclear April27, 2017 Docket No:
50-424 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D.C. 20555-0001 B. Keith Taber Vice President VogUe Units 1-2 Vogtle Electric Generating Plant - Unit 1 Licensee Event Report 2017-002-00 7821 River RD Waynesboro GA. 30830 706-848-0002 tel 706-848-3321 fax NL-17-0664 Wiring Error results in Automatic Actuation of a Safety System Ladies and Gentlemen:
In accordance with the requirements of 10 CFR 50.73(a)(2)(iv)(A), Southern Nuclear Operating Company is submitting the enclosed Licensee Event Report, 2017-002-00 for Vogtle Electric Generating Plant Unit 1. This letter contains no NRC commitments. If you have any questions, please contact Dam Sutton at (706) 848-1428.
B. Keith Taber Vice President - Plant Vogtle Units 1 &2 - SNC BKT/KCW Enclosure: Unit 1 Licensee Event Report 2017-002-00 cc:
Southern Nuclear Operating Company Mr. S. E. Kuczynski, Chairman, President & CEO Mr. D. G. Bast, Executive Vice President & Chief Nuclear Officer Mr. R. D. Gayheart, Fleet Operations General Manager Mr. M. D. Meier, Vice President-Regulatory Affairs Mr. B. J. Adams, Vice President-Engineering Mr. D. D. Sutton, Regulatory Affairs Manager-Vogtle 1 & 2 RType: CVC7000 U. S. Nuclear Regulatory Commission Ms. C. Haney, Regional Administrator Mr. M. D. Orenak, NRR Project Manager-Vogtle 1 & 2 Mr. M. F. Endress, Senior Resident Inspector-Vogtle 1 & 2
Vogtle Electric Generating Plant-Unit 1 Licensee Event Report 2017-002-00 Wiring Labeling Error results in Automatic Actuation of a Safety System Enclosure Unit 1 Licensee Event Report 2017-002-00
NRC FORM 366 (04-2!J17)
U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150*0104 EXPIRES: 0313112020
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(See Page 2 for required number of digits/characters for each block)
{See NUREG-1 022, R.3 for Instruction and guidance for completing this form httpJ/www. nrc.qov/readinq-rm/doc-collections/nureqs/staff/sr1 022/r3l)
- 1. FACILITY NAME Vogtle Electric Generating Plant the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection.
- 2. DOCKET NUMBER 05000424 i.
PAGE 1 OF2
- 4. TITLE
~irina.Error.results,ln.Automatic.Actuati~a..Safetv_fulstem.
- 5. EVENT DATE i
- 6. LER NUMBER
- 7. REPORT DATE
- 8. OTHE'!_FACILITIES INV~O_L_V_ED ____ -i t---f
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!FACILITY NAME DOCKET NUMBER MONTH I DAY I YEAR I YEAR SEQUENTIAL REV MONTH! DAYRR I
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NUMBER NO. r-Jo'ln j i<JSOOO t-3-r-~-r 2017 l 20171 _
002
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!.FACILITY NAME
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- 9. OPERATING MODE
- 11. THIS REPORT IS SUBMITlED PURSUANT TO lHE REQUIREMENTS OF 10 CFR §: Check all that apply) 0 20.2201(b) 0 20.2203(a){3)(1) 0 50.73(a)(2)(ii)(A) 0 50.73(a)(2)(viii)(A) 0 20.2201(d) 0 20.2203(a)(3)(ii) 0 50.73(a)(2)(ii)(B) 0 50.73(a)(2)(viii)(B) 0 20.2203(a)(1) 0 20.2203(a)(4) 0 50.73(a)(2)(111) 0 50.73(a)(2)(1x)(A) 0 20.2203(aX2)(1) 0 50.36(c)(1)(i)(A)
~ 50.73(a)(2)(iv)(A) 0 50.73(a)(2)(x)
- 10. POWER LEVEL 0 20.2203(a)(2)(ii) 0 50.36{c)(1)(11)(A) 0 50.73(a)(2)(v)(A) 0 73.71(a)(4) 0 20.2203(a)(2)(11i) 0 50.36(c)(2) 0 50.73(a)(2)(v)(B) 0 73.71(a)(5) 100 0 20.2203(a)(2)(1v) 0 50.46(a)(3)(il) 0 50.73(a)(2)(v)(C) 0 73.77(a)(1) 0 20.2203(a)(2)(v) 0 50.73(a)(2)(i)(A) 0 50.73(a)(2)(v)(D) 0 73.77(a)(2)(1) 0 20.2203(a)(2)(vi) 0 50.73(a)(2)(1)(B) 0 50.73(a)(2)(vii) 0 73.77(a)(2)(ii) 0 50.73(a)(2)(1)(C) 00THER Specify in Abstract below or In NRC Form 366A
- 12. LICENSEE CONTACT FOR THIS LER LICENSEE CONTACT lret.EPHONE NUMBER (Include Area Coda}
- oom Sutton, Regulate~ Affairs Manager, Vogtle Electric Generating Plant ll_os-848-1428
- 13. COMPI.£JE ONE UNE FOR EACH COMPONENT FAILURE DESCRIBED IN TliiS REPORT ____ _
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I MANU-I REPORTAB~E I
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- lr"-REPORTABLE
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- 14. SUPPLEME~TAL REPOJT EXPECTEJ---
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SUBMISSION 0 YES (If yes, complete 15. EXPECTED SUBMISSION DATE)
[81 NO 1
1 1
i DATE I
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ABSTRACT (Umit to 1400 spaces, I.e., approximately 15 single-spaced typewritten Hnes)
On March 17, 2017, at approximately 1517 EDT, during refueling operations on Unit 1, power was being restored to the Open Phase system for the 1-B Reserve Auxiliary Transformer (RAT). During restoration, a valid undervoltage actuation signal was sent to the 1-B Emergency Diesel Generator (EDG). The EDG automatically started and tied to the safety bus.
This undervoltage condition was caused by a wiring error in the Open Phase system to the 1-B RAT which resulted in an improper restoration after work on the 1-B RAT.
Unit 1 was defueled at the time and remained so throughout the event. There was no change in the decay heat removal for he plant.
Because this event resulted in the automatic actuation of a system listed in 10 CFR 50. 73(a)(2)(iv)(B), this event is reportable under 10 CFR 50.73(a)(2)(iv)(A). This event had no adverse effect on the health and safety of the public, and is of very low safety significance.
Unit 2 was unaffected. 4 27 2017(04-2017)
U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES: 3/31/2020
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\\~li LICENSEE EVENT REPORT {LER)
CONTINUATION SHEET (See NUREG-1 022, R.3 for Instruction and guidance for completing this form http ://www.nrc.gov/readino-m~/doc-collections/nuregslstaff/sr1 022/r31)
, the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection.
____ I
- 2. DOCKETNUMBER r-05000-424
- 1. FACILITY NAME
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- 3. LER NUVIBER
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SEQUENTIAL Vogtle Electric Generating Plant I
NARRAT_N_E__
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A
Event Description
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NUMBER
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- - oo2 REV NO.
- - 00 On March 17, 2017, at approximately 1517 EDT, Unit 1 was in refueling outage 1 R20 with the unit defueled. After work had been performed on the 1-B Reserve Auxiliary Transformer (RAT) and during power restoration, a valid undervoltage actuation signal was sent to the 1-B Emergency Diesel Generator (EDG). The EDG started and automatically tied to the electrical safety bus. Once the issue was identified and understood by the operators, the EDG was secured and the electrical safety bus was transferred to the appropriate offsite power source. The reactor was defueled at the time of the event and remained so throughout the event. Decay heat was removed via the Spent Fuel Pool (SFP) cooling system, to the Component Cooling Water System, to the Nuclear Service Cooling Water system and finally, to the atmosphere.
This report is required per 10CFR50.73(a)(2)(iv)(A) due to an automatic actuation of the Emergency AC power system.
B. Cause of Event
The cause of the event was a wiring error of the Open Phase system alarm and trip circuitry to the RAT. This caused the improper restoration sequence and the valid undervoltage actuation signal to be sent to the EDG as power was being restored to the Open Phase system. The EDG properly detected the undervoltage condition and responded per design.
C. Safety Assessment
The EDG properly started and loaded the safety bus as required. At no time was decay heat removal lost to the Spent Fuel Pool, which was the only location on that unit that required decay heat removal during the event.
Because all safety systems performed their safety function, the safety significance of the event is considered very low.
D. Corrective Actions
The wiring error was discovered using a continuity check during the post-event troubleshooting. The wires from the Open Phase system to the 1-B RAT were found mislabeled and landed on the wrong terminals. The wiring error was subsequently corrected and an extent of condition review was performed to verify proper labels and continuity and no other errors were found.
E. Previous Similar Events
None NRC FORM 3668 (04-2017)